51
|
Bicket A, Mehrabi P, Naydenova Z, Wong V, Donaldson L, Stagljar I, Coe IR. Novel regulation of equlibrative nucleoside transporter 1 (ENT1) by receptor-stimulated Ca2+-dependent calmodulin binding. Am J Physiol Cell Physiol 2016; 310:C808-20. [PMID: 27009875 DOI: 10.1152/ajpcell.00243.2015] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Accepted: 03/09/2016] [Indexed: 01/25/2023]
Abstract
Equilibrative nucleoside transporters (ENTs) facilitate the flux of nucleosides, such as adenosine, and nucleoside analog (NA) drugs across cell membranes. A correlation between adenosine flux and calcium-dependent signaling has been previously reported; however, the mechanistic basis of these observations is not known. Here we report the identification of the calcium signaling transducer calmodulin (CaM) as an ENT1-interacting protein, via a conserved classic 1-5-10 motif in ENT1. Calcium-dependent human ENT1-CaM protein interactions were confirmed in human cell lines (HEK293, RT4, U-87 MG) using biochemical assays (HEK293) and the functional assays (HEK293, RT4), which confirmed modified nucleoside uptake that occurred in the presence of pharmacological manipulations of calcium levels and CaM function. Nucleoside and NA drug uptake was significantly decreased (∼12% and ∼39%, respectively) by chelating calcium (EGTA, 50 μM; BAPTA-AM, 25 μM), whereas increasing intracellular calcium (thapsigargin, 1.5 μM) led to increased nucleoside uptake (∼26%). Activation of N-methyl-d-aspartate (NMDA) receptors (in U-87 MG) by glutamate (1 mM) and glycine (100 μM) significantly increased nucleoside uptake (∼38%) except in the presence of the NMDA receptor antagonist, MK-801 (50 μM), or CaM antagonist, W7 (50 μM). These data support the existence of a previously unidentified novel receptor-dependent regulatory mechanism, whereby intracellular calcium modulates nucleoside and NA drug uptake via CaM-dependent interaction of ENT1. These findings suggest that ENT1 is regulated via receptor-dependent calcium-linked pathways resulting in an alteration of purine flux, which may modulate purinergic signaling and influence NA drug efficacy.
Collapse
Affiliation(s)
- Alex Bicket
- Department of Biology, York University, Toronto, Canada
| | - Pedram Mehrabi
- Department of Biology, York University, Toronto, Canada; Department of Medical Biophysics, University of Toronto, Toronto, Canada
| | - Zlatina Naydenova
- Department of Chemistry and Biology, Ryerson University, Toronto, Canada
| | - Victoria Wong
- Donnelly Centre, Department of Biochemistry and Department of Molecular Genetics, University of Toronto, Toronto, Canada
| | | | - Igor Stagljar
- Donnelly Centre, Department of Biochemistry and Department of Molecular Genetics, University of Toronto, Toronto, Canada
| | - Imogen R Coe
- Department of Biology, York University, Toronto, Canada; Department of Chemistry and Biology, Ryerson University, Toronto, Canada;
| |
Collapse
|
52
|
Black JC, Whetstine JR. Tipping the lysine methylation balance in disease. Biopolymers 2016; 99:127-35. [PMID: 23175387 DOI: 10.1002/bip.22136] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Revised: 08/01/2012] [Accepted: 08/02/2012] [Indexed: 12/28/2022]
Abstract
Genomic instability is a major contributing factor to the development and onset of diseases such as cancer. Emerging evidence has demonstrated that maintaining the proper balance of histone lysine methylation is critical to preserve genomic integrity. Genome-wide association studies, gene sequencing, and genome-wide mapping approaches have helped identify mutations, copy number changes, and aberrant gene regulation of lysine methyltransferases (KMTs) and demethylases (KDMs) associated with cancer and cognitive disorders. Structural analysis of KMTs and KDMs has demonstrated the drugability of these enzymes and has led to the discovery of small molecule inhibitors. Use of these inhibitors has allowed better understanding of the biochemical properties of KMTs and KDMs and demonstrated potential for therapeutic use. This review will highlight the methyl modifications, KMTs and KDMs associated with cancer and neurological disorders and how KMT and KDM and the potential for treatment of these conditions with small molecule inhibitors.
Collapse
Affiliation(s)
- Joshua C Black
- Massachusetts General Hospital Cancer Center and Department of Medicine, Harvard Medical School, 13th Street, Charlestown, MA 02129
| | | |
Collapse
|
53
|
ACF chromatin-remodeling complex mediates stress-induced depressive-like behavior. Nat Med 2015; 21:1146-53. [PMID: 26390241 PMCID: PMC4598281 DOI: 10.1038/nm.3939] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Accepted: 08/11/2015] [Indexed: 02/08/2023]
Abstract
Improved treatment for major depressive disorder (MDD) remains elusive because of the limited understanding of its underlying biological mechanisms. It is likely that stress-induced maladaptive transcriptional regulation in limbic neural circuits contributes to the development of MDD, possibly through epigenetic factors that regulate chromatin structure. We establish that persistent upregulation of the ACF (ATP-utilizing chromatin assembly and remodeling factor) ATP-dependent chromatin-remodeling complex, occurring in the nucleus accumbens of stress-susceptible mice and depressed humans, is necessary for stress-induced depressive-like behaviors. We found that altered ACF binding after chronic stress was correlated with altered nucleosome positioning, particularly around the transcription start sites of affected genes. These alterations in ACF binding and nucleosome positioning were associated with repressed expression of genes implicated in susceptibility to stress. Together, our findings identify the ACF chromatin-remodeling complex as a critical component in the development of susceptibility to depression and in regulating stress-related behaviors.
Collapse
|
54
|
Gurnot C, Martin-Subero I, Mah SM, Weikum W, Goodman SJ, Brain U, Werker JF, Kobor MS, Esteller M, Oberlander TF, Hensch TK. Prenatal antidepressant exposure associated with CYP2E1 DNA methylation change in neonates. Epigenetics 2015; 10:361-72. [PMID: 25891251 DOI: 10.1080/15592294.2015.1026031] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Some but not all neonates are affected by prenatal exposure to serotonin reuptake inhibitor antidepressants (SRI) and maternal mood disturbances. Distinguishing the impact of these 2 exposures is challenging and raises critical questions about whether pharmacological, genetic, or epigenetic factors can explain the spectrum of reported outcomes. Using unbiased DNA methylation array measurements followed by a detailed candidate gene approach, we examined whether prenatal SRI exposure was associated with neonatal DNA methylation changes and whether such changes were associated with differences in birth outcomes. Prenatal SRI exposure was first associated with increased DNA methylation status primarily at CYP2E1(β(Non-exposed) = 0.06, β(SRI-exposed) = 0.30, FDR = 0); however, this finding could not be distinguished from the potential impact of prenatal maternal depressed mood. Then, using pyrosequencing of CYP2E1 regulatory regions in an expanded cohort, higher DNA methylation status--both the mean across 16 CpG sites (P < 0.01) and at each specific CpG site (P < 0.05)--was associated with exposure to lower 3rd trimester maternal depressed mood symptoms only in the SRI-exposed neonates, indicating a maternal mood x SRI exposure interaction. In addition, higher DNA methylation levels at CpG2 (P = 0.04), CpG9 (P = 0.04) and CpG10 (P = 0.02), in the interrogated CYP2E1 region, were associated with increased birth weight independently of prenatal maternal mood, SRI drug exposure, or gestational age at birth. Prenatal SRI antidepressant exposure and maternal depressed mood were associated with altered neonatal CYP2E1 DNA methylation status, which, in turn, appeared to be associated with birth weight.
Collapse
Affiliation(s)
- Cécile Gurnot
- a Center for Brain Science; Department of Molecular Cellular Biology; Harvard University ; Cambridge , MA , USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
55
|
Shen EY, Jiang Y, Mao W, Futai K, Hock H, Akbarian S. Cognition and mood-related behaviors in L3mbtl1 null mutant mice. PLoS One 2015; 10:e0121252. [PMID: 25849281 PMCID: PMC4388653 DOI: 10.1371/journal.pone.0121252] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Accepted: 01/31/2015] [Indexed: 01/22/2023] Open
Abstract
Alterations in histone lysine methylation and epigenetic regulators of gene expression could play a role in the neurobiology and treatment of patients diagnosed with mood spectrum disorder, including depression and anxiety. Mutations and altered expression of various lysine methyltransferases (KMTs) and demethylases (KDMs) have been linked to changes in motivational and emotional behaviors in preclinical model systems. However, it is not known whether regulators operating downstream of histone lysine methylation could affect mood-related behavior. Malignant Brain Tumor (MBT) domain 'chromatin reader' proteins bind to methylated histone lysine residues and associate with chromatin remodeling complexes to facilitate or repress gene expression. MBT proteins, including the founding member, L3mbtl1, maintain high levels of expression in neurons of the mature brain. Here, we exposed L3mbtl1 null mutant mice to a wide range of tests exploring cognition and mood-relevant behaviors at baseline and in the context of social isolation, as a stressor to elicit depression-related behavior in susceptible mice. L3mbtl1 loss-of-function was associated with significant decreases in depression and and anxiety in some of the behavioral paradigms. This was not associated with a more generalized neurological dysfunction because cognition and memory remained unaltered in comparison to controls. These findings warrant further investigations on the role of MBT chromatin reader proteins in the context of emotional and affective behaviors.
Collapse
Affiliation(s)
- Erica Y. Shen
- Department of Psychiatry, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, New York, 10029, United States of America
| | - Yan Jiang
- Department of Psychiatry, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, New York, 10029, United States of America
| | - Wenjie Mao
- Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester, Massachusetts, 01604, United States of America
| | - Kensuke Futai
- Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester, Massachusetts, 01604, United States of America
| | - Hanno Hock
- Cancer Center and Center for Regenerative Medicine, Massachusetts General Hospital, Boston, Massachusetts, 02114, United States of America
| | - Schahram Akbarian
- Department of Psychiatry, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, New York, 10029, United States of America
- * E-mail:
| |
Collapse
|
56
|
Bharadwaj R, Peter CJ, Jiang Y, Roussos P, Vogel-Ciernia A, Shen EY, Mitchell AC, Mao W, Whittle C, Dincer A, Jakovcevski M, Pothula V, Rasmussen TP, Giakoumaki SG, Bitsios P, Sherif A, Gardner PD, Ernst P, Ghose S, Sklar P, Haroutunian V, Tamminga C, Myers RH, Futai K, Wood MA, Akbarian S. Conserved higher-order chromatin regulates NMDA receptor gene expression and cognition. Neuron 2014; 84:997-1008. [PMID: 25467983 PMCID: PMC4258154 DOI: 10.1016/j.neuron.2014.10.032] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/14/2014] [Indexed: 12/17/2022]
Abstract
Three-dimensional chromosomal conformations regulate transcription by moving enhancers and regulatory elements into spatial proximity with target genes. Here we describe activity-regulated long-range loopings bypassing up to 0.5 Mb of linear genome to modulate NMDA glutamate receptor GRIN2B expression in human and mouse prefrontal cortex. Distal intronic and 3' intergenic loop formations competed with repressor elements to access promoter-proximal sequences, and facilitated expression via a "cargo" of AP-1 and NRF-1 transcription factors and TALE-based transcriptional activators. Neuronal deletion or overexpression of Kmt2a/Mll1 H3K4- and Kmt1e/Setdb1 H3K9-methyltransferase was associated with higher-order chromatin changes at distal regulatory Grin2b sequences and impairments in working memory. Genetic polymorphisms and isogenic deletions of loop-bound sequences conferred liability for cognitive performance and decreased GRIN2B expression. Dynamic regulation of chromosomal conformations emerges as a novel layer for transcriptional mechanisms impacting neuronal signaling and cognition.
Collapse
Affiliation(s)
- Rahul Bharadwaj
- Friedman Brain Institute and Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Cyril J Peter
- Friedman Brain Institute and Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Yan Jiang
- Friedman Brain Institute and Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Panos Roussos
- Friedman Brain Institute and Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; Institute for Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; James J. Peters Veterans Affairs Medical Center, Bronx, New York, NY 10468, USA
| | - Annie Vogel-Ciernia
- Department of Neurobiology and Behavior, University of California at Irvine, Irvine, CA 92697, USA
| | - Erica Y Shen
- Friedman Brain Institute and Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Amanda C Mitchell
- Friedman Brain Institute and Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Wenjie Mao
- Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester, MA 01604, USA
| | - Catheryne Whittle
- Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester, MA 01604, USA
| | - Aslihan Dincer
- Friedman Brain Institute and Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | | | - Venu Pothula
- Friedman Brain Institute and Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Theodore P Rasmussen
- Department of Pharmaceutical Sciences and U.Conn Stem Cell Institute, University of Connecticut, Storrs, CT 06269, USA
| | - Stella G Giakoumaki
- Department of Psychiatry, University of Crete, 71003 Iraklion, Greece; Department of Psychology, University of Crete, 71003 Iraklion, Greece
| | - Panos Bitsios
- Computational Medicine Laboratory, Institute of Computer Science, Foundation for Research and Technology Hellas, 71003 Iraklion, Greece; Department of Psychiatry, University of Crete, 71003 Iraklion, Greece
| | - Ajfar Sherif
- Friedman Brain Institute and Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Paul D Gardner
- Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester, MA 01604, USA
| | - Patricia Ernst
- Department of Genetics and Department of Microbiology and Immunology, Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA
| | - Subroto Ghose
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Pamela Sklar
- Friedman Brain Institute and Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; Institute for Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Vahram Haroutunian
- Friedman Brain Institute and Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; James J. Peters Veterans Affairs Medical Center, Bronx, New York, NY 10468, USA
| | - Carol Tamminga
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Richard H Myers
- Department of Neurology, Boston University, Boston, MA 02118, USA
| | - Kensuke Futai
- Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester, MA 01604, USA
| | - Marcelo A Wood
- Department of Neurobiology and Behavior, University of California at Irvine, Irvine, CA 92697, USA
| | - Schahram Akbarian
- Friedman Brain Institute and Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
| |
Collapse
|
57
|
Cho S, Park JS, Kang YK. AGO2 and SETDB1 cooperate in promoter-targeted transcriptional silencing of the androgen receptor gene. Nucleic Acids Res 2014; 42:13545-56. [PMID: 25183519 PMCID: PMC4267665 DOI: 10.1093/nar/gku788] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
In mammals, RNA interference is primarily a post-transcriptional mechanism. Evidence has accumulated for additional role in transcriptional gene silencing (TGS) but the question for a good paradigm for small interfering antigene RNA (agRNA)-induced chromatin modification remains unanswered. Here, we show that SETDB1, a histone H3-lysine 9 (H3K9)-specific methyltransferase, cooperates with Argonaute-2 (AGO2) and plays an essential role in agRNA-induced TGS. The androgen receptor (AR) gene was transcriptionally silenced by agRNA targeted to its promoter, and we show that this repression was mitigated by knockdown of SETDB1 or AGO2. Chromatin immunoprecipitation demonstrated that agRNA-driven AGO2 was first targeted to the AR promoter, followed by SETDB1. SIN3A and HDAC1/2, the components of the SIN3-HDAC complex, immunoprecipitated with SETDB1, and localized at the agRNA-targeted promoter. Agreeing with the presence of SETDB1, trimethyl-H3K9 was enriched in the AR promoter. Both EZH2 and trimethyl-H3K27 were also present in the targeted locus; accordingly, EZH2 immunoprecipitated with SETDB1. DNA methylation level was not significantly changed, suggesting the absence of de novo methylating activity in agRNA-induced AR promoter. Our results demonstrate that SETDB1, together with AGO2, plays an essential role in TGS through recruiting chromatin remodeler and/or other modifiers, consequently creating a repressive chromatin milieu at the targeted promoter.
Collapse
Affiliation(s)
- Sunwha Cho
- Development and Differentiation Research Center, KRIBB, 111 Gwahangno, Yuseong-gu, Daejeon 305-806, South Korea Department of Functional Genomics, University of Science and Technology (UST), 113 Gwahangno, Yuseong-gu, 305-333 Daejeon, South Korea
| | - Jung Sun Park
- Development and Differentiation Research Center, KRIBB, 111 Gwahangno, Yuseong-gu, Daejeon 305-806, South Korea
| | - Yong-Kook Kang
- Development and Differentiation Research Center, KRIBB, 111 Gwahangno, Yuseong-gu, Daejeon 305-806, South Korea Department of Functional Genomics, University of Science and Technology (UST), 113 Gwahangno, Yuseong-gu, 305-333 Daejeon, South Korea
| |
Collapse
|
58
|
Mitchell AC, Bharadwaj R, Whittle C, Krueger W, Mirnics K, Hurd Y, Rasmussen T, Akbarian S. The genome in three dimensions: a new frontier in human brain research. Biol Psychiatry 2014; 75:961-9. [PMID: 23958183 PMCID: PMC3925763 DOI: 10.1016/j.biopsych.2013.07.015] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Revised: 06/16/2013] [Accepted: 07/10/2013] [Indexed: 12/21/2022]
Abstract
Less than 1.5% of the human genome encodes protein. However, vast portions of the human genome are subject to transcriptional and epigenetic regulation, and many noncoding regulatory DNA elements are thought to regulate the spatial organization of interphase chromosomes. For example, chromosomal "loopings" are pivotal for the orderly process of gene expression, by enabling distal regulatory enhancer or silencer elements to directly interact with proximal promoter and transcription start sites, potentially bypassing hundreds of kilobases of interspersed sequence on the linear genome. To date, however, epigenetic studies in the human brain are mostly limited to the exploration of DNA methylation and posttranslational modifications of the nucleosome core histones. In contrast, very little is known about the regulation of supranucleosomal structures. Here, we show that chromosome conformation capture, a widely used approach to study higher-order chromatin, is applicable to tissue collected postmortem, thereby informing about genome organization in the human brain. We introduce chromosome conformation capture protocols for brain and compare higher-order chromatin structures at the chromosome 6p22.2-22.1 schizophrenia and bipolar disorder susceptibility locus, and additional neurodevelopmental risk genes, (DPP10, MCPH1) in adult prefrontal cortex and various cell culture systems, including neurons derived from reprogrammed skin cells. We predict that the exploration of three-dimensional genome architectures and function will open up new frontiers in human brain research and psychiatric genetics and provide novel insights into the epigenetic risk architectures of regulatory noncoding DNA.
Collapse
Affiliation(s)
- Amanda C. Mitchell
- Departments of Psychiatry and Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY
| | - Rahul Bharadwaj
- Departments of Psychiatry and Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY,Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester MA
| | - Catheryne Whittle
- Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester MA
| | - Winfried Krueger
- Center for Regenerative Biology and Department of Pharmaceutical Sciences, University of Connecticut, Storrs, CT
| | - Karoly Mirnics
- Department of Psychiatry, Vanderbilt University, Nashville, TN
| | - Yasmin Hurd
- Departments of Psychiatry and Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY
| | - Theodore Rasmussen
- Center for Regenerative Biology and Department of Pharmaceutical Sciences, University of Connecticut, Storrs, CT
| | - Schahram Akbarian
- Departments of Psychiatry and Neuroscience , Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, New York; Brudnick Neuropsychiatric Research Institute , University of Massachusetts Medical School, Worcester, Massachusetts.
| |
Collapse
|
59
|
Plattner F, Hernández A, Kistler TM, Pozo K, Zhong P, Yuen EY, Tan C, Hawasli AH, Cooke SF, Nishi A, Guo A, Wiederhold T, Yan Z, Bibb JA. Memory enhancement by targeting Cdk5 regulation of NR2B. Neuron 2014; 81:1070-1083. [PMID: 24607229 DOI: 10.1016/j.neuron.2014.01.022] [Citation(s) in RCA: 103] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/08/2014] [Indexed: 12/22/2022]
Abstract
UNLABELLED Many psychiatric and neurological disorders are characterized by learning and memory deficits, for which cognitive enhancement is considered a valid treatment strategy. The N-methyl-D-aspartate receptor (NMDAR) is a prime target for the development of cognitive enhancers because of its fundamental role in learning and memory. In particular, the NMDAR subunit NR2B improves synaptic plasticity and memory when overexpressed in neurons. However, NR2B regulation is not well understood and no therapies potentiating NMDAR function have been developed. Here, we show that serine 1116 of NR2B is phosphorylated by cyclin-dependent kinase 5 (Cdk5). Cdk5-dependent NR2B phosphorylation is regulated by neuronal activity and controls the receptor's cell surface expression. Disrupting NR2B-Cdk5 interaction via a small interfering peptide (siP) increases NR2B surface levels, facilitates synaptic transmission, and improves memory formation in vivo. Our results reveal a regulatory mechanism critical to NR2B function that can be targeted for the development of cognitive enhancers. VIDEO ABSTRACT
Collapse
Affiliation(s)
- Florian Plattner
- Department of Psychiatry, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Adan Hernández
- Department of Psychiatry, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Tara M Kistler
- Department of Psychiatry, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Karine Pozo
- Department of Psychiatry, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Ping Zhong
- Department of Physiology and Biophysics, State University of New York at Buffalo, Buffalo, NY 14214, USA
| | - Eunice Y Yuen
- Department of Physiology and Biophysics, State University of New York at Buffalo, Buffalo, NY 14214, USA
| | - Chunfeng Tan
- Department of Psychiatry, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Ammar H Hawasli
- Department of Psychiatry, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Sam F Cooke
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Akinori Nishi
- Department of Pharmacology, School of Medicine, Kurume University, Fukuoka 830-0011, Japan
| | - Ailan Guo
- Cell Signaling Technology, CNS Development, Danvers, MA 01923, USA
| | | | - Zhen Yan
- Department of Physiology and Biophysics, State University of New York at Buffalo, Buffalo, NY 14214, USA
| | - James A Bibb
- Department of Psychiatry, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Neurology and Neurotherapeutics, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Harold C. Simmons Comprehensive Cancer Center, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
| |
Collapse
|
60
|
Dynorphin up-regulation in the dentate granule cell mossy fiber pathway following chronic inhibition of GluN2B-containing NMDAR is associated with increased CREB (Ser 133) phosphorylation, but is independent of BDNF/TrkB signaling pathways. Mol Cell Neurosci 2014; 60:63-71. [PMID: 24769103 DOI: 10.1016/j.mcn.2014.04.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Revised: 03/06/2014] [Accepted: 04/14/2014] [Indexed: 12/21/2022] Open
Abstract
Emerging evidence suggests that neuronal responses to N-methyl-d-aspartate (NMDAR) activation/inactivation are influenced by subunit composition. For example, activation of synaptic NMDAR (comprised of GluN2A>GluN2B) phosphorylates cAMP-response-element-binding protein (CREB) at Ser 133, induces BDNF expression and promotes neuronal survival. Activation of extrasynaptic NMDAR (comprised of GluN2B>GluN2) dephosphorylates CREB (Ser 133), reduces BDNF expression and triggers neuronal death. These results led us to hypothesize that chronic inhibition of GluN2B-containing NMDAR would increase CREB (Ser 133) phosphorylation, increase BDNF levels and subsequently alter downstream dynorphin (DYN) and neuropeptide Y (NPY) expression. We focused on DYN and NPY because these neuropeptides can decrease excitatory neurotransmission and seizure occurrence and we reported previously that seizure-like events are reduced following chronic treatment with GluN2B antagonists. Consistent with our hypothesis, chronic treatment (17-21days) of hippocampal slice cultures with the GluN2B-selective antagonists ifenprodil or Ro25,6981 increased both CREB (Ser 133) phosphorylation and granule cell mossy fiber pathway DYN expression. Similar treatment with the non-subtype-selective NMDAR antagonists d-APV or memantine had no significant effect on either CREB (Ser 133) phosphorylation or DYN expression. In contrast to our hypothesis, BDNF levels were decreased following chronic treatment with Ro25,6981, but not ifenprodil, d-APV or memantine. Blockade of BDNF actions and TrkB activation did not significantly augment hilar DYN expression in vehicle-treated cultures and had no effect in Ro25,6981 treated cultures. These findings suggest that chronic exposure to GluN2B-selective NMDAR antagonists increased DYN expression through a putatively pCREB-dependent, but BDNF/TrkB-independent mechanism.
Collapse
|
61
|
Abstract
Recent data support the view that epigenetic processes play a role in memory consolidation and help to transmit acquired memories even across generations in a Lamarckian manner. Drugs that target the epigenetic machinery were found to enhance memory function in rodents and ameliorate disease phenotypes in models for brain diseases such as Alzheimer's disease, Chorea Huntington, Depression or Schizophrenia. In this review, I will give an overview on the current knowledge of epigenetic processes in memory function and brain disease with a focus on Morbus Alzheimer as the most common neurodegenerative disease. I will address the question whether an epigenetic therapy could indeed be a suitable therapeutic avenue to treat brain diseases and discuss the necessary steps that should help to take neuroepigenetic research to the next level.
Collapse
Affiliation(s)
- Andre Fischer
- Department of Psychiatry and Psychotherapy, University Medical Center Göttingen, Göttingen, Germany
| |
Collapse
|
62
|
Abstract
Growing evidence supports the hypothesis that epigenetics is a key mechanism through which environmental exposures interact with an individual’s genetic constitution to determine risk for depression throughout life. Epigenetics, in its broadest meaning, refers to stable changes in gene expression that are mediated via altered chromatin structure without modification of DNA sequence. According to this hypothesis, severe stress triggers changes—in vulnerable individuals—in chromatin structure at particular genomic loci in the brain’s limbic regions, which drive sustained changes in gene expression that contribute to episodes of depression. A corollary of this hypothesis is that such stress-induced epigenetic modifications also occur early in life and help determine an individual’s lifetime vulnerability or resistance to subsequent stressful events.
Collapse
Affiliation(s)
- Eric J. Nestler
- Fishberg Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, New York; Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, New York
| |
Collapse
|
63
|
Schoch H, Abel T. Transcriptional co-repressors and memory storage. Neuropharmacology 2014; 80:53-60. [PMID: 24440532 DOI: 10.1016/j.neuropharm.2014.01.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Revised: 01/03/2014] [Accepted: 01/04/2014] [Indexed: 12/26/2022]
Abstract
Epigenetic modifications are a central mechanism for regulating chromatin structure and gene expression in the brain. A wide array of histone- and DNA-modifying enzymes have been identified as critical regulators of neuronal function, memory formation, and as causative agents in neurodevelopmental and neuropsychiatric disorders. Chromatin modifying enzymes are frequently incorporated into large multi-protein co-activator and co-repressor complexes, where the activity of multiple enzymes is both spatially and temporally coordinated. In this review, we discuss negative regulation of gene expression by co-repressor complexes, and the role of co-repressors and their binding partners in neuronal function, memory, and disease.
Collapse
Affiliation(s)
- Hannah Schoch
- Cell and Molecular Biology Graduate Group, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Ted Abel
- Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, USA.
| |
Collapse
|
64
|
Mosbech MB, Olsen ASB, Neess D, Ben-David O, Klitten LL, Larsen J, Sabers A, Vissing J, Nielsen JE, Hasholt L, Klein AD, Tsoory MM, Hjalgrim H, Tommerup N, Futerman AH, Møller RS, Færgeman NJ. Reduced ceramide synthase 2 activity causes progressive myoclonic epilepsy. Ann Clin Transl Neurol 2014; 1:88-98. [PMID: 25356388 PMCID: PMC4212479 DOI: 10.1002/acn3.28] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Accepted: 12/04/2013] [Indexed: 12/19/2022] Open
Abstract
Objective Ceramides are precursors of complex sphingolipids (SLs), which are important for normal functioning of both the developing and mature brain. Altered SL levels have been associated with many neurodegenerative disorders, including epilepsy, although few direct links have been identified between genes involved in SL metabolism and epilepsy. Methods We used quantitative real-time PCR, Western blotting, and enzymatic assays to determine the mRNA, protein, and activity levels of ceramide synthase 2 (CERS2) in fiibroblasts isolated from parental control subjects and from a patient diagnosed with progressive myoclonic epilepsy (PME). Mass spectrometry and fluorescence microscopy were used to examine the effects of reduced CERS2 activity on cellular lipid composition and plasma membrane functions. Results We identify a novel 27 kb heterozygous deletion including the CERS2 gene in a proband diagnosed with PME. Compared to parental controls, levels of CERS2 mRNA, protein, and activity were reduced by ˜50% in fibroblasts isolated from this proband, resulting in significantly reduced levels of ceramides and sphingomyelins containing the very long-chain fatty acids C24:0 and C26:0. The change in SL composition was also reflected in a reduction in cholera toxin B immunofluorescence, indicating that membrane composition and function are altered. Interpretation We propose that reduced levels of CERS2, and consequently diminished levels of ceramides and SLs containing very long-chain fatty acids, lead to development of PME.
Collapse
Affiliation(s)
- Mai-Britt Mosbech
- Department of Biochemistry and Molecular Biology, University of Southern Denmark Odense M, DK-5230, Denmark
| | - Anne S B Olsen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark Odense M, DK-5230, Denmark
| | - Ditte Neess
- Department of Biochemistry and Molecular Biology, University of Southern Denmark Odense M, DK-5230, Denmark
| | - Oshrit Ben-David
- Department of Biological Chemistry, Weizmann Institute of Science Rehovot, 76100, Israel
| | - Laura L Klitten
- The Danish Epilepsy Centre, Filadelfia Dianalund, DK-4293, Denmark
| | - Jan Larsen
- The Danish Epilepsy Centre, Filadelfia Dianalund, DK-4293, Denmark ; Department of Cellular and Molecular Medicine, The Panum Institute, University of Copenhagen Copenhagen, DK-2100, Denmark
| | - Anne Sabers
- Department of Neurology, Rigshospitalet, University of Copenhagen Copenhagen, DK-2100, Denmark
| | - John Vissing
- Department of Neurology, Rigshospitalet, University of Copenhagen Copenhagen, DK-2100, Denmark
| | - Jørgen E Nielsen
- Neurogenetics Clinic, Danish Dementia Research Centre, Department of Neurology, Rigshospitalet, Copenhagen University Hospital Copenhagen, DK-2100, Denmark
| | - Lis Hasholt
- Department of Cellular and Molecular Medicine, The Panum Institute, University of Copenhagen Copenhagen, DK-2100, Denmark
| | - Andres D Klein
- Department of Biological Chemistry, Weizmann Institute of Science Rehovot, 76100, Israel
| | - Michael M Tsoory
- Behavioral and Physiological Phenotyping Unit, Department of Veterinary Resources, Weizmann Institute of Science Rehovot, 76100, Israel
| | - Helle Hjalgrim
- The Danish Epilepsy Centre, Filadelfia Dianalund, DK-4293, Denmark ; Institute for Regional Health Services, University of Southern Denmark Odense, Denmark
| | - Niels Tommerup
- Department of Cellular and Molecular Medicine, The Panum Institute, University of Copenhagen Copenhagen, DK-2100, Denmark
| | - Anthony H Futerman
- Department of Biological Chemistry, Weizmann Institute of Science Rehovot, 76100, Israel
| | - Rikke S Møller
- The Danish Epilepsy Centre, Filadelfia Dianalund, DK-4293, Denmark ; Institute for Regional Health Services, University of Southern Denmark Odense, Denmark
| | - Nils J Færgeman
- Department of Biochemistry and Molecular Biology, University of Southern Denmark Odense M, DK-5230, Denmark
| |
Collapse
|
65
|
Gavin DP, Floreani C. Epigenetics of schizophrenia: an open and shut case. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2014; 115:155-201. [PMID: 25131545 DOI: 10.1016/b978-0-12-801311-3.00005-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
During the last decade and a half, there has been an explosion of data regarding epigenetic changes in schizophrenia. Most initial studies have suggested that schizophrenia is characterized by an overly restrictive chromatin state based on increases in transcription silencing histone modifications and DNA methylation at schizophrenia candidate gene promoters and increases in the expression of enzymes that catalyze their formation. However, recent studies indicate that the pathology is more complex. This complexity may greatly impact pharmacological approaches directed at targeting epigenetic abnormalities in schizophrenia. The current review explores epigenetic studies of schizophrenia and what this can tell us about the underlying pathophysiology. We hypothesize based on recent studies that it is also plausible that drugs that further restrict chromatin may be efficacious.
Collapse
Affiliation(s)
- David P Gavin
- Department of Psychiatry, University of Illinois at Chicago, Chicago, Illinois, USA; Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois, USA.
| | - Christina Floreani
- Department of Psychiatry, University of Illinois at Chicago, Chicago, Illinois, USA; Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois, USA
| |
Collapse
|
66
|
Abstract
Stress response is considered to have adaptive value for organisms faced with stressful condition. Chronic stress however adversely affects the physiology and may lead to neuropsychiatric disorders. Repeated stressful events in animal models have been shown to cause long-lasting changes in neural circuitries at molecular, cellular, and physiological level, leading to disorders of mood as well as cognition. Molecular studies in recent years have implicated diverse epigenetic mechanisms, including histone modifications, DNA methylation, and noncoding RNAs, that underlie dysregulation of genes in the affected neural circuitries in chronic stress-induced pathophysiology. A review of the myriad epigenetic regulatory mechanisms associated with neural and behavioral responses in animal models of stress-induced neuropsychiatric disorders is presented here. The review also deals with clinical evidence of the epigenetic dysregulation of genes in psychiatric disorders where chronic stress appears to underlie the etiopathology.
Collapse
|
67
|
Vogel-Ciernia A, Wood MA. Neuron-specific chromatin remodeling: a missing link in epigenetic mechanisms underlying synaptic plasticity, memory, and intellectual disability disorders. Neuropharmacology 2013; 80:18-27. [PMID: 24140580 DOI: 10.1016/j.neuropharm.2013.10.002] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2013] [Revised: 09/29/2013] [Accepted: 10/04/2013] [Indexed: 01/09/2023]
Abstract
Long-term memory formation requires the coordinated regulation of gene expression. Until recently nucleosome remodeling, one of the major epigenetic mechanisms for controlling gene expression, had been largely unexplored in the field of neuroscience. Nucleosome remodeling is carried out by chromatin remodeling complexes (CRCs) that interact with DNA and histones to physically alter chromatin structure and ultimately regulate gene expression. Human exome sequencing and gene wide association studies have linked mutations in CRC subunits to intellectual disability disorders, autism spectrum disorder and schizophrenia. However, how mutations in CRC subunits were related to human cognitive disorders was unknown. There appears to be both developmental and adult specific roles for the neuron specific CRC nBAF (neuronal Brg1/hBrm Associated Factor). nBAF regulates gene expression required for dendritic arborization during development, and in the adult, contributes to long-term potentiation, a form of synaptic plasticity, and long-term memory. We propose that the nBAF complex is a novel epigenetic mechanism for regulating transcription required for long-lasting forms of synaptic plasticity and memory processes and that impaired nBAF function may result in human cognitive disorders.
Collapse
Affiliation(s)
- Annie Vogel-Ciernia
- University of California, Irvine, Department of Neurobiology & Behavior, Irvine, CA, USA; Center for the Neurobiology of Learning & Memory, Irvine, CA, USA
| | - Marcelo A Wood
- University of California, Irvine, Department of Neurobiology & Behavior, Irvine, CA, USA; Center for the Neurobiology of Learning & Memory, Irvine, CA, USA.
| |
Collapse
|
68
|
Abstract
This review highlights recent discoveries that have shaped the emerging viewpoints in the field of epigenetic influences in the central nervous system (CNS), focusing on the following questions: (i) How is the CNS shaped during development when precursor cells transition into morphologically and molecularly distinct cell types, and is this event driven by epigenetic alterations?; ii) How do epigenetic pathways control CNS function?; (iii) What happens to "epigenetic memory" during aging processes, and do these alterations cause CNS dysfunction?; (iv) Can one restore normal CNS function by manipulating the epigenome using pharmacologic agents, and will this ameliorate aging-related neurodegeneration? These and other still unanswered questions remain critical to understanding the impact of multifaceted epigenetic machinery on the age-related dysfunction of CNS.
Collapse
Affiliation(s)
- Yue-Qiang Zhao
- />Buck Institute for Research on Aging, 8001 Redwood Boulevard, Novato, CA 94945-1400 USA
- />Department of Plastic Surgery, Renmin Hospital of Wuhan University, Wuhan, China
| | - I. King Jordan
- />School of Biology, Georgia Institute of Technology, Atlanta, GA USA
- />PanAmerican Bioinformatics Institute, Santa Marta, Magdalena Colombia
| | - Victoria V. Lunyak
- />Buck Institute for Research on Aging, 8001 Redwood Boulevard, Novato, CA 94945-1400 USA
| |
Collapse
|
69
|
Individual differences in novelty seeking predict subsequent vulnerability to social defeat through a differential epigenetic regulation of brain-derived neurotrophic factor expression. J Neurosci 2013; 33:11048-60. [PMID: 23825410 DOI: 10.1523/jneurosci.0199-13.2013] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Some personality traits, including novelty seeking, are good predictors of vulnerability to stress-related mood disorders in both humans and rodents. While high-novelty-seeking rats [high responders (HRs)] are vulnerable to the induction of depressive-like symptoms by social defeat stress, low-novelty-seeking rats [low responders (LRs)] are not. Here, we show that such individual differences are critically regulated by hippocampal BDNF. While LR animals exhibited an increase in BDNF levels following social defeat, HR individuals did not. This difference in hippocampal BDNF expression promoted the vulnerability of HR and the resilience of LR rats. Indeed, preventing activation of BDNF signaling by infusing the BDNF scavenger TrkB-Fc into the dentate gyrus of the hippocampus of LR rats led to social defeat-induced social avoidance, whereas its activation in HR rats by the TrkB agonist 7,8-dihydroxyflavone promoted social approach. Along with the changes in BDNF expression following defeat, we report in LR animals a downregulation of the inactive BDNF receptor TrkB.T1, associated with an activation of CREB through Akt-mediated signaling, but not MSK1-mediated signaling. In HR animals, none of these molecules were affected by social defeat. Importantly, the BDNF upregulation involved an epigenetically controlled transcription of bdnf exon VI, associated with a coherent regulation of relevant epigenetic factors. Altogether, our data support the importance of hippocampal BDNF regulation in response to stressful events. Moreover, we identify a specific and adaptive regulation of bdnf exon VI in the hippocampus as a critical regulator of stress resilience, and strengthen the importance of epigenetic factors in mediating stress-induced adaptive and maladaptive responses in different individuals.
Collapse
|
70
|
Parkel S, Lopez-Atalaya JP, Barco A. Histone H3 lysine methylation in cognition and intellectual disability disorders. Learn Mem 2013; 20:570-9. [PMID: 24045506 DOI: 10.1101/lm.029363.112] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Recent research indicates that epigenetic mechanisms and, in particular, the post-translational modification (PTM) of histones may contribute to memory encoding and storage. Among the dozens of possible histone PTMs, the methylation/demethylation of lysines in the N-terminal tail of histone H3 exhibits particularly strong links with cognitive abilities. First, the persistence and tight association with distinct transcriptional states of the gene make these modifications particularly suitable for being part of the molecular underpinnings of memory storage. Second, correlative evidence indicates that the methylation/demethylation of lysines in histone H3 is actively regulated during memory processes. Third, several enzymes regulating these PTMs are associated with intellectual disability disorders. We review here these three lines of evidence and discuss the potential role of epigenetic mechanisms centered on the methylation of lysine residues on histone H3 in neuroplasticity and neurodevelopmental disorders associated with intellectual disability.
Collapse
Affiliation(s)
- Sven Parkel
- Instituto de Neurociencias, Universidad Miguel Hernández-Consejo Superior de Investigaciones Científicas, Sant Joan d'Alacant 03550, Alicante, Spain
| | | | | |
Collapse
|
71
|
Akbarian S, Beeri MS, Haroutunian V. Epigenetic determinants of healthy and diseased brain aging and cognition. JAMA Neurol 2013; 70:711-8. [PMID: 23571692 DOI: 10.1001/jamaneurol.2013.1459] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
A better understanding of normal and diseased brain aging and cognition will have a significant public health impact, given that the oldest-old persons older than 85 years of age represent the fastest-growing segment in the population in developed countries, with more than 30 million new cases of dementia predicted to occur worldwide each year by 2040. Dysregulation of gene expression and, more generally, genome organization and function are thought to contribute to age-related declines in cognition. Remarkably, nearly all neuronal nuclei that reside in an aged brain had permanently exited from the cell cycle during prenatal development, and DNA methylation and histone modifications and other molecular constituents of the epigenome are likely to play a critical role in the maintenance of neuronal health and function throughout the entire lifespan. Here, we provide an overview of age-related changes in the brain's chromatin structures, highlight potential epigenetic drug targets for cognitive decline and age-related neurodegenerative disease, and discuss opportunities and challenges when studying epigenetic biomarkers in aging research.
Collapse
Affiliation(s)
- Schahram Akbarian
- Department of Psychiatry, Mount Sinai School of Medicine, New York, New York 10029, USA.
| | | | | |
Collapse
|
72
|
Abstract
Mood disorders are common and debilitating conditions characterized in part by profound deficits in reward-related behavioural domains. A recent literature has identified important structural and functional alterations within the brain's reward circuitry--particularly in the ventral tegmental area-nucleus accumbens pathway--that are associated with symptoms such as anhedonia and aberrant reward-associated perception and memory. This Review synthesizes recent data from human and rodent studies from which emerges a circuit-level framework for understanding reward deficits in depression. We also discuss some of the molecular and cellular underpinnings of this framework, ranging from adaptations in glutamatergic synapses and neurotrophic factors to transcriptional and epigenetic mechanisms.
Collapse
Affiliation(s)
- Scott J Russo
- Fishberg Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, New York 10029, USA. scott.russo@mssm. edu
| | | |
Collapse
|
73
|
Bharadwaj R, Jiang Y, Mao W, Jakovcevski M, Dincer A, Krueger W, Garbett K, Whittle C, Tushir JS, Liu J, Sequeira A, Vawter MP, Gardner PD, Casaccia P, Rasmussen T, Bunney WE, Mirnics K, Futai K, Akbarian S. Conserved chromosome 2q31 conformations are associated with transcriptional regulation of GAD1 GABA synthesis enzyme and altered in prefrontal cortex of subjects with schizophrenia. J Neurosci 2013; 33:11839-51. [PMID: 23864674 PMCID: PMC3713726 DOI: 10.1523/jneurosci.1252-13.2013] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Revised: 05/16/2013] [Accepted: 06/12/2013] [Indexed: 01/07/2023] Open
Abstract
Little is known about chromosomal loopings involving proximal promoter and distal enhancer elements regulating GABAergic gene expression, including changes in schizophrenia and other psychiatric conditions linked to altered inhibition. Here, we map in human chromosome 2q31 the 3D configuration of 200 kb of linear sequence encompassing the GAD1 GABA synthesis enzyme gene locus, and we describe a loop formation involving the GAD1 transcription start site and intergenic noncoding DNA elements facilitating reporter gene expression. The GAD1-TSS(-50kbLoop) was enriched with nucleosomes epigenetically decorated with the transcriptional mark, histone H3 trimethylated at lysine 4, and was weak or absent in skin fibroblasts and pluripotent stem cells compared with neuronal cultures differentiated from them. In the prefrontal cortex of subjects with schizophrenia, GAD1-TSS(-50kbLoop) was decreased compared with controls, in conjunction with downregulated GAD1 expression. We generated transgenic mice expressing Gad2 promoter-driven green fluorescent protein-conjugated histone H2B and confirmed that Gad1-TSS(-55kbLoop), the murine homolog to GAD1-TSS(-50kbLoop), is a chromosomal conformation specific for GABAergic neurons. In primary neuronal culture, Gad1-TSS(-55kbLoop) and Gad1 expression became upregulated when neuronal activity was increased. We conclude that 3D genome architectures, including chromosomal loopings for promoter-enhancer interactions involved in the regulation of GABAergic gene expression, are conserved between the rodent and primate brain, and subject to developmental and activity-dependent regulation, and disordered in some cases with schizophrenia. More broadly, the findings presented here draw a connection between noncoding DNA, spatial genome architecture, and neuronal plasticity in development and disease.
Collapse
Affiliation(s)
- Rahul Bharadwaj
- Graduate School of Biomedical Sciences and
- Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester, Massachusetts 01655
| | - Yan Jiang
- Departments of Psychiatry and Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, New York 10029
| | - Wenjie Mao
- Graduate School of Biomedical Sciences and
- Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester, Massachusetts 01655
| | | | - Aslihan Dincer
- Departments of Psychiatry and Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, New York 10029
| | - Winfried Krueger
- Center for Regenerative Biology and Department of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut 06269
| | - Krassimira Garbett
- Department of Psychiatry, Vanderbilt University, Nashville, Tennessee 37232, and
| | - Catheryne Whittle
- Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester, Massachusetts 01655
| | - Jogender Singh Tushir
- Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester, Massachusetts 01655
| | - Jia Liu
- Departments of Psychiatry and Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, New York 10029
| | - Adolfo Sequeira
- Department of Psychiatry and Human Behavior, University of California, Irvine, California 92697
| | - Marquis P. Vawter
- Department of Psychiatry and Human Behavior, University of California, Irvine, California 92697
| | - Paul D. Gardner
- Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester, Massachusetts 01655
| | - Patrizia Casaccia
- Departments of Psychiatry and Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, New York 10029
| | - Theodore Rasmussen
- Center for Regenerative Biology and Department of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut 06269
| | - William E. Bunney
- Department of Psychiatry and Human Behavior, University of California, Irvine, California 92697
| | - Karoly Mirnics
- Department of Psychiatry, Vanderbilt University, Nashville, Tennessee 37232, and
| | - Kensuke Futai
- Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester, Massachusetts 01655
| | - Schahram Akbarian
- Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester, Massachusetts 01655
- Departments of Psychiatry and Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, New York 10029
| |
Collapse
|
74
|
Telese F, Gamliel A, Skowronska-Krawczyk D, Garcia-Bassets I, Rosenfeld MG. "Seq-ing" insights into the epigenetics of neuronal gene regulation. Neuron 2013; 77:606-23. [PMID: 23439116 PMCID: PMC3736682 DOI: 10.1016/j.neuron.2013.01.034] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/24/2013] [Indexed: 01/08/2023]
Abstract
The epigenetic control of neuronal gene expression patterns has emerged as an underlying regulatory mechanism for neuronal function, identity, and plasticity, in which short- to long-lasting adaptation is required to dynamically respond and process external stimuli. To achieve a comprehensive understanding of the physiology and pathology of the brain, it becomes essential to understand the mechanisms that regulate the epigenome and transcriptome in neurons. Here, we review recent advances in the study of regulated neuronal gene expression, which are dramatically expanding as a result of the development of new and powerful contemporary methodologies, based on next-generation sequencing. This flood of new information has already transformed our understanding of many biological processes and is now driving discoveries elucidating the molecular mechanisms of brain function in cognition, behavior, and disease and may also inform the study of neuronal identity, diversity, and neuronal reprogramming.
Collapse
Affiliation(s)
- Francesca Telese
- Department of Medicine, School of Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | | | | | | | | |
Collapse
|
75
|
Snyder MA, Gao WJ. NMDA hypofunction as a convergence point for progression and symptoms of schizophrenia. Front Cell Neurosci 2013; 7:31. [PMID: 23543703 PMCID: PMC3608949 DOI: 10.3389/fncel.2013.00031] [Citation(s) in RCA: 163] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Accepted: 03/11/2013] [Indexed: 01/05/2023] Open
Abstract
Schizophrenia is a disabling mental illness that is now recognized as a neurodevelopmental disorder. It is likely that genetic risk factors interact with environmental perturbations to affect normal brain development and that this altered trajectory results in a combination of positive, negative, and cognitive symptoms. Although the exact pathophysiology of schizophrenia is unknown, the N-methyl-D-aspartate receptor (NMDAR), a major glutamate receptor subtype, has received great attention. Proper expression and regulation of NMDARs in the brain is critical for learning and memory processes as well as cortical plasticity and maturation. Evidence from both animal models and human studies implicates a dysfunction of NMDARs both in disease progression and symptoms of schizophrenia. Furthermore, mutations in many of the known genetic risk factors for schizophrenia suggest that NMDAR hypofunction is a convergence point for schizophrenia. In this review, we discuss how disrupted NMDAR function leads to altered neurodevelopment that may contribute to the progression and development of symptoms for schizophrenia, particularly cognitive deficits. We review the shared signaling pathways among the schizophrenia susceptibility genes DISC1, neuregulin1, and dysbindin, focusing on the AKT/GSK3β pathway, and how their mutations and interactions can lead to NMDAR dysfunction during development. Additionally, we explore what open questions remain and suggest where schizophrenia research needs to move in order to provide mechanistic insight into the cause of NMDAR dysfunction, as well as generate possible new avenues for therapeutic intervention.
Collapse
Affiliation(s)
- Melissa A Snyder
- Department of Neurobiology and Anatomy, Drexel University College of Medicine Philadelphia, PA, USA
| | | |
Collapse
|
76
|
Abstract
Although tricyclic antidepressants rapidly activate monoaminergic neurotransmission, these drugs must be administered chronically to alleviate symptoms of depression. This observation suggests that molecular mechanisms downstream of monoamine receptor activation, which include the induction of gene transcription, underlie chronic antidepressant-induced changes in behavior. Here we show that methyl-CpG-binding protein 2 (MeCP2) regulates behavioral responses to chronic antidepressant treatment. Imipramine administration induces phosphorylation of MeCP2 at Ser421 (pMeCP2) selectively in the nucleus accumbens and the lateral habenula, two brain regions important for depressive-like behaviors. To test the role of pMeCP2 in depressive-like behaviors, we used male mice that bear a germ-line mutation knocked into the X-linked Mecp2 locus that changes Ser421 to a nonphosphorylatable Ala residue (S421A). MeCP2 S421A knock-in (KI) mice showed increased immobility in forced-swim and tail-suspension tests compared with their wild-type (WT) littermates. However, immobility of both MeCP2 WT and KI mice in forced swim was reduced by acute administration of imipramine, demonstrating that loss of pMeCP2 does not impair acute pharmacological sensitivity to this drug. After chronic social defeat stress, chronic administration of imipramine significantly improved social interaction in the MeCP2 WT mice. In contrast, the MeCP2 KI mice did not respond to chronic imipramine administration. These data suggest novel roles for pMeCP2 in the sensitivity to stressful stimuli and demonstrate that pMeCP2 is required for the effects of chronic imipramine on depressive-like behaviors induced by chronic social defeat stress.
Collapse
|
77
|
Abstract
Many cellular constituents in the human brain permanently exit from the cell cycle during pre- or early postnatal development, but little is known about epigenetic regulation of neuronal and glial epigenomes during maturation and aging, including changes in mood and psychosis spectrum disorders and other cognitive or emotional disease. Here, we summarize the current knowledge base as it pertains to genome organization in the human brain, including the regulation of DNA cytosine methylation and hydroxymethylation, and a subset of (altogether >100) residue-specific histone modifications associated with gene expression, and silencing and various other functional chromatin states. We propose that high-resolution mapping of epigenetic markings in postmortem brain tissue or neural cultures derived from induced pluripotent cells (iPS), in conjunction with transcriptome profiling and whole-genome sequencing, will increasingly be used to define the molecular pathology of specific cases diagnosed with depression, schizophrenia, autism, or other major psychiatric disease. We predict that these highly integrative explorations of genome organization and function will provide an important alternative to conventional approaches in human brain studies, which mainly are aimed at uncovering group effects by diagnosis but generally face limitations because of cohort size.
Collapse
|
78
|
Sun H, Kennedy PJ, Nestler EJ. Epigenetics of the depressed brain: role of histone acetylation and methylation. Neuropsychopharmacology 2013; 38:124-37. [PMID: 22692567 PMCID: PMC3521990 DOI: 10.1038/npp.2012.73] [Citation(s) in RCA: 268] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2012] [Revised: 04/12/2012] [Accepted: 04/16/2012] [Indexed: 12/17/2022]
Abstract
Major depressive disorder is a chronic, remitting syndrome involving widely distributed circuits in the brain. Stable alterations in gene expression that contribute to structural and functional changes in multiple brain regions are implicated in the heterogeneity and pathogenesis of the illness. Epigenetic events that alter chromatin structure to regulate programs of gene expression have been associated with depression-related behavior, antidepressant action, and resistance to depression or 'resilience' in animal models, with increasing evidence for similar mechanisms occurring in postmortem brains of depressed humans. In this review, we discuss recent advances in our understanding of epigenetic contributions to depression, in particular the role of histone acetylation and methylation, which are revealing novel mechanistic insight into the syndrome that may aid in the development of novel targets for depression treatment.
Collapse
Affiliation(s)
- HaoSheng Sun
- Fishberg Department of Neuroscience and Friedman Brain Institute, School of Medicine, New York, NY, USA
| | - Pamela J Kennedy
- Fishberg Department of Neuroscience and Friedman Brain Institute, School of Medicine, New York, NY, USA
| | - Eric J Nestler
- Fishberg Department of Neuroscience and Friedman Brain Institute, School of Medicine, New York, NY, USA
| |
Collapse
|
79
|
Millan MJ. An epigenetic framework for neurodevelopmental disorders: from pathogenesis to potential therapy. Neuropharmacology 2012; 68:2-82. [PMID: 23246909 DOI: 10.1016/j.neuropharm.2012.11.015] [Citation(s) in RCA: 151] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2012] [Revised: 11/11/2012] [Accepted: 11/22/2012] [Indexed: 12/12/2022]
Abstract
Neurodevelopmental disorders (NDDs) are characterized by aberrant and delayed early-life development of the brain, leading to deficits in language, cognition, motor behaviour and other functional domains, often accompanied by somatic symptoms. Environmental factors like perinatal infection, malnutrition and trauma can increase the risk of the heterogeneous, multifactorial and polygenic disorders, autism and schizophrenia. Conversely, discrete genetic anomalies are involved in Down, Rett and Fragile X syndromes, tuberous sclerosis and neurofibromatosis, the less familiar Phelan-McDermid, Sotos, Kleefstra, Coffin-Lowry and "ATRX" syndromes, and the disorders of imprinting, Angelman and Prader-Willi syndromes. NDDs have been termed "synaptopathies" in reference to structural and functional disturbance of synaptic plasticity, several involve abnormal Ras-Kinase signalling ("rasopathies"), and many are characterized by disrupted cerebral connectivity and an imbalance between excitatory and inhibitory transmission. However, at a different level of integration, NDDs are accompanied by aberrant "epigenetic" regulation of processes critical for normal and orderly development of the brain. Epigenetics refers to potentially-heritable (by mitosis and/or meiosis) mechanisms controlling gene expression without changes in DNA sequence. In certain NDDs, prototypical epigenetic processes of DNA methylation and covalent histone marking are impacted. Conversely, others involve anomalies in chromatin-modelling, mRNA splicing/editing, mRNA translation, ribosome biogenesis and/or the regulatory actions of small nucleolar RNAs and micro-RNAs. Since epigenetic mechanisms are modifiable, this raises the hope of novel therapy, though questions remain concerning efficacy and safety. The above issues are critically surveyed in this review, which advocates a broad-based epigenetic framework for understanding and ultimately treating a diverse assemblage of NDDs ("epigenopathies") lying at the interface of genetic, developmental and environmental processes. This article is part of the Special Issue entitled 'Neurodevelopmental Disorders'.
Collapse
Affiliation(s)
- Mark J Millan
- Unit for Research and Discovery in Neuroscience, IDR Servier, 125 chemin de ronde, 78290 Croissy sur Seine, Paris, France.
| |
Collapse
|
80
|
Tan SL, Nishi M, Ohtsuka T, Matsui T, Takemoto K, Kamio-Miura A, Aburatani H, Shinkai Y, Kageyama R. Essential roles of the histone methyltransferase ESET in the epigenetic control of neural progenitor cells during development. Development 2012; 139:3806-16. [PMID: 22991445 DOI: 10.1242/dev.082198] [Citation(s) in RCA: 100] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
In the developing brain, neural progenitor cells switch differentiation competency by changing gene expression profiles that are governed partly by epigenetic control, such as histone modification, although the precise mechanism is unknown. Here we found that ESET (Setdb1), a histone H3 Lys9 (H3K9) methyltransferase, is highly expressed at early stages of mouse brain development but downregulated over time, and that ablation of ESET leads to decreased H3K9 trimethylation and the misregulation of genes, resulting in severe brain defects and early lethality. In the mutant brain, endogenous retrotransposons were derepressed and non-neural gene expression was activated. Furthermore, early neurogenesis was severely impaired, whereas astrocyte formation was enhanced. We conclude that there is an epigenetic role of ESET in the temporal and tissue-specific gene expression that results in proper control of brain development.
Collapse
Affiliation(s)
- Siok-Lay Tan
- Institute for Virus Research, Kyoto University, Kyoto 606-8507, Japan
| | | | | | | | | | | | | | | | | |
Collapse
|
81
|
Histone methylation in the nervous system: functions and dysfunctions. Mol Neurobiol 2012; 47:740-56. [PMID: 23161382 DOI: 10.1007/s12035-012-8376-4] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2012] [Accepted: 11/04/2012] [Indexed: 11/26/2022]
Abstract
Chromatin remodeling is a key epigenetic process controlling the regulation of gene transcription. Local changes of chromatin architecture can be achieved by post-translational modifications of histones such as methylation, acetylation, phosphorylation, ubiquitination, sumoylation, and ADP-ribosylation. These changes are dynamic and allow for rapid repression or de-repression of specific target genes. Chromatin remodeling enzymes are largely involved in the control of cellular differentiation, and loss or gain of function is often correlated with pathological events. For these reasons, research on chromatin remodeling enzymes is currently very active and rapidly expanding, these enzymes representing very promising targets for the design of novel therapeutics in different areas of medicine including oncology and neurology. In this review, we focus on histone methylation in the nervous system. We provide an overview on mammalian histone methyltransferases and demethylases and their mechanisms of action, and we discuss their roles in the development of the nervous system and their involvement in neurodevelopmental, neurodegenerative, and behavioral disorders.
Collapse
|
82
|
Cukier HN, Lee JM, Ma D, Young JI, Mayo V, Butler BL, Ramsook SS, Rantus JA, Abrams AJ, Whitehead PL, Wright HH, Abramson RK, Haines JL, Cuccaro ML, Pericak-Vance MA, Gilbert JR. The expanding role of MBD genes in autism: identification of a MECP2 duplication and novel alterations in MBD5, MBD6, and SETDB1. Autism Res 2012; 5:385-97. [PMID: 23055267 DOI: 10.1002/aur.1251] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2012] [Accepted: 08/02/2012] [Indexed: 01/09/2023]
Abstract
The methyl-CpG-binding domain (MBD) gene family was first linked to autism over a decade ago when Rett syndrome, which falls under the umbrella of autism spectrum disorders (ASDs), was revealed to be predominantly caused by MECP2 mutations. Since that time, MECP2 alterations have been recognized in idiopathic ASD patients by us and others. Individuals with deletions across the MBD5 gene also present with ASDs, impaired speech, intellectual difficulties, repetitive behaviors, and epilepsy. These findings suggest that further investigations of the MBD gene family may reveal additional associations related to autism. We now describe the first study evaluating individuals with ASD for rare variants in four autosomal MBD family members, MBD5, MBD6, SETDB1, and SETDB2, and expand our initial screening in the MECP2 gene. Each gene was sequenced over all coding exons and evaluated for copy number variations in 287 patients with ASD and an equal number of ethnically matched control individuals. We identified 186 alterations through sequencing, approximately half of which were novel (96 variants, 51.6%). We identified 17 ASD specific, nonsynonymous variants, four of which were concordant in multiplex families: MBD5 Tyr1269Cys, MBD6 Arg883Trp, MECP2 Thr240Ser, and SETDB1 Pro1067del. Furthermore, a complex duplication spanning of the MECP2 gene was identified in two brothers who presented with developmental delay and intellectual disability. From our studies, we provide the first examples of autistic patients carrying potentially detrimental alterations in MBD6 and SETDB1, thereby demonstrating that the MBD gene family potentially plays a significant role in rare and private genetic causes of autism.
Collapse
Affiliation(s)
- Holly N Cukier
- John P. Hussman Institute for Human Genomics, University of Miami, Miller School of Medicine, Miami, FL 33136, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
83
|
Vialou V, Feng J, Robison AJ, Nestler EJ. Epigenetic mechanisms of depression and antidepressant action. Annu Rev Pharmacol Toxicol 2012; 53:59-87. [PMID: 23020296 DOI: 10.1146/annurev-pharmtox-010611-134540] [Citation(s) in RCA: 184] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Epigenetic mechanisms, which control chromatin structure and function, mediate changes in gene expression that occur in response to diverse stimuli. Recent research has established that environmental events and behavioral experience induce epigenetic changes at particular gene loci and that these changes help shape neuronal plasticity and function and hence behavior. Some of these changes can be stable and can even persist for a lifetime. Increasing evidence supports the hypothesis that aberrations in chromatin remodeling and subsequent effects on gene expression within limbic brain regions contribute to the pathogenesis of depression and other stress-related disorders such as post-traumatic stress disorder and other anxiety syndromes. Likewise, the gradually developing but persistent therapeutic effects of antidepressant medications may be achieved in part via epigenetic mechanisms. This review discusses recent advances in our understanding of the epigenetic regulation of stress-related disorders and focuses on three distinct aspects of stress-induced epigenetic pathology: the effects of stress and antidepressant treatment during adulthood, the lifelong effects of early-life stress on subsequent stress vulnerability, and the possible transgenerational transmission of stress-induced abnormalities.
Collapse
Affiliation(s)
- Vincent Vialou
- Fishberg Department of Neuroscience and Friedman Brain Institute, Mount Sinai School of Medicine, New York, New York 10029, USA
| | | | | | | |
Collapse
|
84
|
Connor CM, Dincer A, Straubhaar J, Houston IB, Akbarian S, Akbarian S. Maternal immune activation alters behavior in adult offspring, with subtle changes in the cortical transcriptome and epigenome. Schizophr Res 2012; 140:175-84. [PMID: 22804924 PMCID: PMC3568668 DOI: 10.1016/j.schres.2012.06.037] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2012] [Revised: 06/21/2012] [Accepted: 06/25/2012] [Indexed: 01/27/2023]
Abstract
Maternal immune activation during prenatal development, including treatment with the viral RNA mimic, polyriboinosinic-polyribocytidilic acid (poly IC), serves as a widely used animal model to induce behavioral deficits reminiscent of schizophrenia and related disease. Here, we report that massive cytokine activation after a single dose of poly IC in the prenatal period is associated with lasting working memory deficits in adult offspring. To explore whether dysregulated gene expression in cerebral cortex, contributes to cognitive dysfunction, we profiled the cortical transcriptome, and in addition, mapped the genome-wide distribution of trimethylated histone H3-lysine 4 (H3K4me3), an epigenetic mark sharply regulated at the 5' end of transcriptional units. However, deep sequencing-based H3K4me3 mapping and mRNA profiling by microarray did not reveal significant alterations in mature cerebral cortex after poly IC exposure at embryonic days E17.5 or E12.5. At a small set of genes (including suppressor of cytokine signaling Socs3), H3K4me3 was sensitive to activation of cytokine signaling in primary cultures from fetal forebrain but adult cortex of saline- and poly IC-exposed mice did not show significant differences. A limited set of transcription start sites (TSS), including Disrupted-in-Schizophrenia 1 (Disc1), a schizophrenia risk gene often implicated in gene-environment interaction models, showed altered H3K4me3 after prenatal poly IC but none of these differences survived after correcting for multiple comparisons. We conclude that prenatal poly IC is associated with cognitive deficits later in life, but without robust alterations in epigenetic regulation of gene expression in the cerebral cortex.
Collapse
Affiliation(s)
- Caroline M Connor
- Department of Psychiatry, Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester MA 01604
| | - Aslihan Dincer
- Department of Psychiatry, Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester MA 01604
| | - Juerg Straubhaar
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester MA 01604
| | - Isaac B Houston
- Department of Psychiatry, Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester MA 01604
| | - Schahram Akbarian
- Department of Psychiatry, Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester MA 01604
| | | |
Collapse
|
85
|
The neurobiology of chromatin-associated mechanisms in the context of psychosisand mood spectrum disorders. Epigenomics 2012. [DOI: 10.1017/cbo9780511777271.036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
|
86
|
Gavin DP, Akbarian S. Epigenetic and post-transcriptional dysregulation of gene expression in schizophrenia and related disease. Neurobiol Dis 2012; 46:255-62. [DOI: 10.1016/j.nbd.2011.12.008] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2011] [Revised: 11/10/2011] [Accepted: 12/04/2011] [Indexed: 12/22/2022] Open
|
87
|
Puckett RE, Lubin FD. Epigenetic mechanisms in experience-driven memory formation and behavior. Epigenomics 2012; 3:649-64. [PMID: 22126252 DOI: 10.2217/epi.11.86] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Epigenetic mechanisms have long been associated with the regulation of gene-expression changes accompanying normal neuronal development and cellular differentiation; however, until recently these mechanisms were believed to be statically quiet in the adult brain. Behavioral neuroscientists have now begun to investigate these epigenetic mechanisms as potential regulators of gene-transcription changes in the CNS subserving synaptic plasticity and long-term memory (LTM) formation. Experimental evidence from learning and memory animal models has demonstrated that active chromatin remodeling occurs in terminally differentiated postmitotic neurons, suggesting that these molecular processes are indeed intimately involved in several stages of LTM formation, including consolidation, reconsolidation and extinction. Such chromatin modifications include the phosphorylation, acetylation and methylation of histone proteins and the methylation of associated DNA to subsequently affect transcriptional gene readout triggered by learning. The present article examines how such learning-induced epigenetic changes contribute to LTM formation and influence behavior. In particular, this article is a survey of the specific epigenetic mechanisms that have been demonstrated to regulate gene expression for both transcription factors and growth factors in the CNS, which are critical for LTM formation and storage, as well as how aberrant epigenetic processing can contribute to psychological states such as schizophrenia and drug addiction. Together, the findings highlighted in this article support a novel role for epigenetic mechanisms in the adult CNS serving as potential key molecular regulators of gene-transcription changes necessary for LTM formation and adult behavior.
Collapse
Affiliation(s)
- Rosemary E Puckett
- Evelyn F McKnight Brain Institute, Department of Neurobiology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | | |
Collapse
|
88
|
Lagali PS, Picketts DJ. Matters of life and death: the role of chromatin remodeling proteins in retinal neuron survival. J Ocul Biol Dis Infor 2012; 4:111-20. [PMID: 23289056 PMCID: PMC3382293 DOI: 10.1007/s12177-012-9080-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2012] [Accepted: 03/05/2012] [Indexed: 12/13/2022] Open
Abstract
Retinal neurons are highly vulnerable to a diverse array of neurotoxic stimuli that leads to their degeneration, which is a major contributor to blindness. This review summarizes the role of epigenetic factors in mediating neuronal homeostasis and survival to protect against cell death and neurodegenerative conditions. Studies in human patients and mouse models implicate numerous chromatin modifications in neuroprotective processes including histone protein acetylation and methylation, DNA methylation, and ATP-dependent nucleosome remodeling. Recent research has begun to uncover specific epigenetic mechanisms invoked by neurotoxic stimuli. Continued investigation in this area will be the key to the generation of therapeutic strategies for the intervention of retinal neurodegenerative diseases.
Collapse
Affiliation(s)
- Pamela S Lagali
- Regenerative Medicine Program, Ottawa Hospital Research Institute, 501 Smyth Road, Ottawa, ON Canada K1H 8L6 ; Department of Biochemistry, Microbiology and Immunology, University of Ottawa, 451 Smyth Road, Ottawa, ON Canada K1H 8M5
| | | |
Collapse
|
89
|
Sharma RP, Gavin DP, Chase KA. Heterochromatin as an incubator for pathology and treatment non-response: implication for neuropsychiatric illness. THE PHARMACOGENOMICS JOURNAL 2012; 12:361-7. [PMID: 22249356 DOI: 10.1038/tpj.2011.64] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Heterochromatin is a higher order assembly that is characterized by a genome-wide distribution, gene-repression, durability and potential to spread. In this light, it is an appealing mechanism to interpret the neurobiology of complex brain disorders such as schizophrenia where downregulation of expression appears to be the norm. H3K9 methylation (H3K9me) can initiate the seeding of a heterochromatin assembly on an inactive or poorly coordinated promoter as a consequence of a decline in transactivators either from disuse or from misuse. H3K9me can extend its influence by spatial spreading through the mechanism of recursively recruiting adapters, such as heterochromatin protein 1 (HP1) homodimers. HP1 itself serves as a platform for other repressive proteins such as DNA methyltransferases. In full color, heterochromatin can occupy genome-wide gene networks, tissue specific ontologies and even rearrange the nuclear architecture. Heterochromatin in the brain is modified by small molecule pharmacology and serves a physiological role in the functioning of dopamine neurons and the construction of memory. From a therapeutic perspective, the durable nature of heterochromatin implies that it may require disassembly before the full genomic-potential of standard pharmacotherapies is achieved, especially in treatment resistant patients.
Collapse
Affiliation(s)
- R P Sharma
- The Psychiatric Institute, University of Illinois at Chicago, Chicago, IL 60612, USA.
| | | | | |
Collapse
|
90
|
Baudry A, Mouillet-Richard S, Launay JM, Kellermann O. New views on antidepressant action. Curr Opin Neurobiol 2011; 21:858-65. [DOI: 10.1016/j.conb.2011.03.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2011] [Revised: 03/31/2011] [Accepted: 03/31/2011] [Indexed: 10/18/2022]
|
91
|
Matamales M, Girault JA. Signaling from the cytoplasm to the nucleus in striatal medium-sized spiny neurons. Front Neuroanat 2011; 5:37. [PMID: 21779236 PMCID: PMC3133824 DOI: 10.3389/fnana.2011.00037] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2011] [Accepted: 06/13/2011] [Indexed: 12/13/2022] Open
Abstract
Striatal medium-sized spiny neurons (MSNs) receive massive glutamate inputs from the cerebral cortex and thalamus and are a major target of dopamine projections. Interaction between glutamate and dopamine signaling is crucial for the control of movement and reward-driven learning, and its alterations are implicated in several neuropsychiatric disorders including Parkinson's disease and drug addiction. Long-lasting forms of synaptic plasticity are thought to depend on transcription of gene products that alter the structure and/or function of neurons. Although multiple signal transduction pathways regulate transcription, little is known about signal transmission between the cytoplasm and the nucleus of striatal neurons and its regulation. Here we review the current knowledge of the signaling cascades that target the nucleus of MSNs, most of which are activated by cAMP and/or Ca(2+). We outline the mechanisms by which signals originating at the plasma membrane and amplified in the cytoplasm are relayed to the nucleus, through the regulation of several protein kinases and phosphatases and transport through the nuclear pore. We also summarize the identified mechanisms of transcription regulation and chromatin remodeling in MSNs that appear to be important for behavioral adaptations, and discuss their relationships with epigenetic regulation.
Collapse
Affiliation(s)
- Miriam Matamales
- UMR-S 839, InsermParis, France
- Université Pierre et Marie CurieParis, France
- Institut du Fer à MoulinParis, France
| | - Jean-Antoine Girault
- UMR-S 839, InsermParis, France
- Université Pierre et Marie CurieParis, France
- Institut du Fer à MoulinParis, France
| |
Collapse
|
92
|
Gavin DP, Chase KA, Sharma RP. Enhancement of psychotherapy using epigenetic modulating drugs. Med Hypotheses 2011; 77:121-4. [PMID: 21504840 DOI: 10.1016/j.mehy.2011.03.042] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2011] [Accepted: 03/23/2011] [Indexed: 12/22/2022]
Abstract
Recent evidence suggests that covalent modifications to the genomic platform in the brain, that is DNA and its surrounding histones, provide a stable potentially lifelong mechanism for remembrance. Consequently, the making and unmaking of memories is accessible through pharmacological manipulations of these modifications. This has implications for psychotherapy and long-term rehabilitation of CNS disorders. We hypothesize that by enhancing learning through pharmacologically manipulating 'epigenetic' parameters, the effects of psychotherapies and rehabilitation can be enhanced.
Collapse
Affiliation(s)
- David P Gavin
- The Psychiatric Institute, Department of Psychiatry, University of Illinois at Chicago, 1601 West Taylor Street, Chicago, IL 60612, USA.
| | | | | |
Collapse
|
93
|
Peter CJ, Akbarian S. Balancing histone methylation activities in psychiatric disorders. Trends Mol Med 2011; 17:372-9. [PMID: 21429800 DOI: 10.1016/j.molmed.2011.02.003] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2010] [Revised: 02/08/2011] [Accepted: 02/09/2011] [Indexed: 01/22/2023]
Abstract
Alterations in histone lysine methylation and other epigenetic regulators of gene expression contribute to changes in brain transcriptomes in mood and psychosis spectrum disorders, including depression and schizophrenia. Genetic association studies and animal models implicate multiple lysine methyltransferases and demethylases in the neurobiology of emotion and cognition. Here, we review the role of histone lysine methylation and transcriptional regulation in normal and diseased neurodevelopment and discuss various methyltransferases and demethylases as potential therapeutic targets in the treatment of neuropsychiatric disease.
Collapse
Affiliation(s)
- Cyril Jayakumar Peter
- Brudnick Neuropsychiatric Research Institute, Department of Psychiatry, University of Massachusetts Medical School, Worcester, MA 01604, USA
| | | |
Collapse
|
94
|
Hollis F, Duclot F, Gunjan A, Kabbaj M. Individual differences in the effect of social defeat on anhedonia and histone acetylation in the rat hippocampus. Horm Behav 2011; 59:331-7. [PMID: 20851702 PMCID: PMC3037445 DOI: 10.1016/j.yhbeh.2010.09.005] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2010] [Revised: 08/12/2010] [Accepted: 09/08/2010] [Indexed: 01/18/2023]
Abstract
Major depression is a growing problem worldwide with variation in symptoms and response to treatment. Individual differences in response to stress may contribute to such observed individual variation in behavior and pathology. Therefore, we investigated depressive-like behavior following exposure to repeated social defeat in a rat model of individual differences in response to novelty. Rats are known to exhibit either high locomotor activity and sustained exploration (high responders, HR) or low activity with minimal exploration (low responders, LR) in a novel environment. We measured anhedonia using the sucrose preference test in HR and LR rats following exposure to social defeat stress or in basal, non-defeated conditions. We then compared histone acetylation in the hippocampus in HR and LR defeat and non-defeated rats and measured mRNA levels of histone deacetylases (HDAC) 3, 4, 5, and Creb binding protein (CBP). We found that basally, HR rats consumed more sucrose solution than LR rats, but reduced consumption after exposure to defeat. LR rats' preference was unaffected by social defeat. We found that HR rats had higher levels of histone acetylation on H3K14 and H2B than LR rats in non-stress conditions. Following defeat, this acetylation pattern changed differentially, with HR rats decreasing acetylation of H3K14 and H2B and LR's increasing acetylation of H3K14. Acetylation on histone H4 decreased following defeat with no individual variation. Basal differences in CBP expression levels may underlie the observed acetylation pattern; however we found no significant effects of defeat in levels of HDACs 3, 4, 5 in the hippocampus.
Collapse
Affiliation(s)
- F Hollis
- Department of Biomedical Sciences, Florida State University College of Medicine, Tallahassee, FL 32306, USA
| | | | | | | |
Collapse
|
95
|
Konopka G. Functional genomics of the brain: uncovering networks in the CNS using a systems approach. WILEY INTERDISCIPLINARY REVIEWS-SYSTEMS BIOLOGY AND MEDICINE 2010; 3:628-48. [PMID: 21197665 DOI: 10.1002/wsbm.139] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The central nervous system (CNS) is undoubtedly the most complex human organ system in terms of its diverse functions, cellular composition, and connections. Attempts to capture this diversity experimentally were the foundation on which the field of neurobiology was built. Until now though, techniques were either painstakingly slow or insufficient in capturing this heterogeneity. In addition, the combination of multiple layers of information needed for a complete picture of neuronal diversity from the epigenome to the proteome requires an even more complex compilation of data. In this era of high-throughput genomics though, the ability to isolate and profile neurons and brain tissue has increased tremendously and now requires less effort. Both microarrays and next-generation sequencing have identified neuronal transcriptomes and signaling networks involved in normal brain development, as well as in disease. However, the expertise needed to organize and prioritize the resultant data remains substantial. A combination of supervised organization and unsupervised analyses are needed to fully appreciate the underlying structure in these datasets. When utilized effectively, these analyses have yielded striking insights into a number of fundamental questions in neuroscience on topics ranging from the evolution of the human brain to neuropsychiatric and neurodegenerative disorders. Future studies will incorporate these analyses with behavioral and physiological data from patients to more efficiently move toward personalized therapeutics.
Collapse
Affiliation(s)
- Genevieve Konopka
- Department of Neurology, University of California, Los Angeles, CA, USA.
| |
Collapse
|
96
|
Jiang Y, Matevossian A, Guo Y, Akbarian S. Setdb1-mediated histone H3K9 hypermethylation in neurons worsens the neurological phenotype of Mecp2-deficient mice. Neuropharmacology 2010; 60:1088-97. [PMID: 20869373 DOI: 10.1016/j.neuropharm.2010.09.020] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2010] [Revised: 09/03/2010] [Accepted: 09/16/2010] [Indexed: 12/26/2022]
Abstract
Rett syndrome (RTT, OMIM # 312750), a neurodevelopmental disorder of early childhood, is primarily caused by mutations in the gene encoding methyl-CpG-binding protein 2 (MECP2). Various molecular functions have been ascribed to MECP2, including the regulation of histone modifications associated with repressive chromatin remodeling, but the role of these mechanisms for the pathophysiology of RTT remains unclear. Here, we explore whether or not neuronal expression of the histone H3-lysine 9 specific methyl-transferase, Setdb1 (Set domain, bifurcated 1)/Eset/Kmt1e, which is normally present only at low levels in differentiated neurons, rescues the RTT-like phenotype of Mecp2-deficient mice. A myc-tagged Setdb1 cDNA was expressed through the tau locus for ubiquitous expression in CNS neurons, or under control of the calcium/calmodulin-dependent protein kinase II (CK) promoter to selectively target postmitotic neurons in forebrain. However, the CK-Setdb1 transgene lead to an enhanced neurological deficit, and the tauSetdb1 allele further shortened life span of mice with a brain-wide deletion of Mecp2 during prenatal development. In contrast, no neurological deficits or premature death was observed in CK-Setdb1 and tauSetdb1 mice expressing wildtype Mecp2. However, levels of trimethylated H3K9 at pericentromeric repeats were fully maintained in differentiated neurons from symptomatic Mecp2 null mutant mice. Based on these results, we draw two conclusions: First, neuronal chromatin in RTT brain is not affected by a generalized deficit in H3K9 trimethylation. Second, artificial up-regulation of this repressive chromatin mark via Setdb1 gene delivery specifically to neurons is harmful for the Mecp2-deficient brain. This article is part of a Special Issue entitled 'Trends in neuropharmacology: in memory of Erminio Costa'.
Collapse
Affiliation(s)
- Yan Jiang
- Brudnick Neuropsychiatric Research Institute, Department of Psychiatry, University of Massachusetts Medical School, 303 Belmont Street, Worcester, MA 01604, USA
| | | | | | | |
Collapse
|